Battery module

ABSTRACT

A battery module includes a cell unit, including a plurality of battery cells disposed on both surfaces of a unit plate, and a case accommodating the cell unit and provided with a cooling device on at least one surface of the case. The unit plate includes a plurality of receiving spaces formed by a plate portion, having a flat surface, and a side portion protruding upwardly and downwardly of the plate portion from both sides of the plate portion. The plurality of battery cells are received in each of the receiving spaces.

CROSS-REFERENCE TO RELATED APPLICATION(S)

This application claims the benefit under 35 USC 119(a) of Korean PatentApplication No. 10-2019-0056206 filed on May 14, 2019 in the KoreanIntellectual Property Office, the entire disclosure of which isincorporated herein by reference for all purposes.

BACKGROUND 1. Field

This application relates to a battery module.

2. Description of Related Art

Unlike primary batteries, secondary batteries may charge and dischargeelectrical energy. Thus, secondary batteries may be applied to variousfields, for example, in the areas of digital cameras, mobile phones,notebook computers, hybrid vehicles, and the like. Examples of secondarybatteries may include nickel-cadmium batteries, nickel-metal hydridebatteries, nickel-hydrogen batteries, lithium secondary batteries, andthe like.

Among such secondary batteries, a large amount of research into lithiumsecondary batteries having a relatively high energy density and arelatively high discharge voltage is in progress. Recently, lithiumsecondary batteries have been manufactured as pouched battery cellshaving flexibility. In this case, the pouched battery cells are providedas a plurality of pouched battery cell modules. The plurality of pouchedbattery cell modules may be configured to be connected and used asbattery modules.

Meanwhile, when the battery module is used for a lengthy period of time,heat may be generated by the battery module. In particular, an internaltemperature of the battery module may rise rapidly, during a chargingoperation thereof. In this case, such an increase in temperature of thebattery module may shorten a lifespan of the battery module, maydecrease efficiency of the battery module, and, in the worst case,ignition or explosion may occur therein.

Therefore, the battery nodule requires a cooling system for cooling thebattery cells accommodated therein. However, in the related art an issuein which cooling efficiency may be significantly low because heatgenerated by the battery cells is not effectively dissipated has beenencountered.

SUMMARY

Example embodiments of the present disclosure provide a battery module,capable of efficiently dissipating heat generated in a battery cell.

A battery module according to example embodiments includes a cell unit,including a plurality of battery cells disposed on both surfaces of aunit plate, and a case accommodating the cell unit and provided with acooling device on at least one surface of the case. The unit plateincludes a plurality of receiving spaces formed by a plate portion,having a flat surface, and a side portion protruding upwardly anddownwardly of the plate portion from both sides of the plate portion.The plurality of battery cells are received in each of the receivingspaces.

In example embodiments, the case may include a first plate disposedabove the cell unit, a second plate disposed below the cell unit, and athird plate disposed on a side portion of the cell unit and includingthe cooling device.

In example embodiments, the side portion may have an external surfacedisposed to oppose the third plate.

In example embodiments, the battery module may further include a heattransfer member disposed between the side portion and the third plate.

In example embodiments, the heat transfer member may be formed of one ofthermal grease, a thermally conductive adhesive, and a pad.

In example embodiments, the third plate may include an internal sideplate disposed to oppose the cell unit, an external side plate disposedoutside of the internal side plate to be in contact with the internalside plate, and a cooling flow path provided between the internal sideplate and the external side plate.

In example embodiments, the third plate may further include areinforcing plate coupled to the external side plate while covering anexternal surface of the external side plate and formed of a materialhaving greater rigidity than that of the external side plate.

In example embodiments, the third plate may be formed of aluminum, andthe reinforcing plate may be formed of an ultrahigh-strength steelsheet.

In example embodiments, in the plate portion of the unit plate, aportion connected to the side portion may be formed to have a largethickness.

BRIEF DESCRIPTION OF DRAWINGS

The above and other aspects, features, and advantages of the presentdisclosure will be more clearly understood from the following detaileddescription, taken in conjunction with the accompanying drawings.

FIG. 1 is a schematic perspective view of a battery module according toexample embodiments of the present disclosure.

FIG. 2 is an exploded perspective view of the battery module illustratedin FIG. 1.

FIG. 3 is an exploded perspective view of a cell unit illustrated inFIG. 2.

FIG. 4 is a partially enlarged plan view of a connection member of FIG.3.

FIG. 5 is a cross-sectional view taken along line I-I′ in FIG. 4.

FIG. 6 is an exploded perspective view of a unit plate and a circuitboard illustrated in FIG. 3.

FIG. 7 is an exploded perspective view of a cell unit and a couplingunit illustrated in FIG. 2.

FIG. 8 is a cross-sectional view taken along line II-II′ in FIG. 1.

DETAILED DESCRIPTION

Prior to the description, it should be understood that the terms used inthe specification and the appended claims should not be construed aslimited to general and dictionary meanings, but should be interpretedbased on the meanings and concepts corresponding to technical aspects ofthe present disclosure on the basis of the principle that the inventoris allowed to define terms appropriately for the best explanation.Therefore, the configurations described in the following descriptionwith reference the accompanying drawings do not represent all technicalconcepts or ideas of the present disclosure but should be considered tobe exemplary embodiments of the present disclosure. It should beunderstood that various modifications and equivalents of the embodimentsmay be devised within the scope of the present invention at the time ofthe filing of the application.

Hereinafter, example embodiments of the present disclosure will bedescribed in detail with reference to the accompanying drawings. In thedrawings, the same elements are denoted by the same reference numeralsas much as possible. Furthermore, detailed descriptions related towell-known functions or configurations may be omitted in order not tounnecessarily obscure subject matters of the present disclosure. For thesame reason, some of the elements in the accompanying drawings areexaggerated, omitted, or shown schematically, and the size of eachelement may not entirely reflect the actual size.

FIG. 1 is a schematic perspective view of a battery module according toexample embodiments, and FIG. 2 is an exploded perspective view of thebattery module illustrated in FIG. 1.

FIG. 3 is an exploded perspective view of a cell unit illustrated inFIG. 2, FIG. 4 is a partially enlarged plan view of a connection memberof FIG. 3, and FIG. 5 is a cross-sectional view taken along line I-I′ inFIG. 4.

FIG. 6 is an exploded perspective view of a unit plate and a circuitboard illustrated in FIG. 3, FIG. 7 is an exploded perspective view of acell unit and a coupling unit illustrated in FIG. 2, and FIG. 8 is across-sectional view taken along line II-II′ in FIG. 1.

Referring to FIGS. 1 to 3, a battery module 100 according to thisembodiment may have a substantially hexahedral shape and may include acell assembly 60, in which a plurality battery cells 10 are coupled toeach other, and a case 40 protecting the cell assembly 60 from theoutside.

The cell assembly 60 includes a plurality of cells units 20 coupled toeach other.

Referring to FIG. 3, the cell unit 20 includes a unit plate 21, aplurality of battery cells 10 stacked on the unit plate 21, and acircuit board 28.

The battery cell 10 may be provided as a plurality of battery cellsstacked side by side, and may have a structure in which electrode leads15 protrude outwardly of a body. The battery cell 10 may be, forexample, a pouched secondary battery.

The battery cell 10 may have a configuration in which an electrodeassembly, not illustrated, is accommodated in a pouch 11.

The electrode assembly may include a plurality of electrode plates and aplurality of electrode tabs, and may be accommodated in the pouch 11.Each of the electrode plates may include a positive electrode plate anda negative electrode plate, and the electrode assembly may have aconfiguration in which the positive electrode plate and the negativeelectrode plate are stacked such that relatively large surfaces opposeeach other with a separator interposed therebetween.

The positive electrode plate and the negative electrode plate may beformed to have structure in which an active material slurry is coated ona current collector. The slurry may be formed by stirring a granularactive material, an auxiliary conductor, a binder, a plasticizer, andthe like, in a state in which a solvent is added.

In the electrode assembly, a plurality of positive electrode plates anda plurality of negative electrode plates may be vertically stacked. Inthis case, the plurality of positive electrode plates and the pluralityof negative electrode plates may be provided with electrode tabs,respectively, and may be in contact with each other with the samepolarity to be in connected to the same electrode lead 15.

In this embodiment, two electrode leads 15 are disposed to face inopposing directions.

The pouch 11 may be formed to have a container shape to provide aninternal space in which the electrode assembly and electrolyte, notillustrated, are accommodated. In this case, a portion of the electrodelead 15 of the electrode assembly may be exposed outwardly of the pouch11.

The pouch 11 may be divided into a sealing portion 202 and anaccommodation portion 204.

The accommodation portion 204 may be formed to have a container shape toprovide an internal space having a rectangular shape. The electrodeassembly and the electrolyte may be accommodated in the internal spaceof the accommodation portion 204.

The sealing portion 202 may be formed to have a flange shape extendingoutwardly of the accommodation portion 204 formed to have the containershape. Therefore, the sealing portion 202 may be disposed to have anedge shape along an external surface of the accommodation portion 204.

A method of bonding sealing portions 202 to each other may be thermalfusion bonding, but the present disclosure is not limited thereto.

In this embodiment, the sealing portion 202 may be divided into a firstsealing portion 2021, in which the electrode leads 15 are disposed, anda second sealing portion 2022 in which the electrode leads 15 are notdisposed.

In this embodiment, since the electrode leads 15 are disposed to face inopposing directions, the two electrode leads 15 are disposed on thesealing portions 202 formed on different sides. Accordingly, the sealingportion 202 provided on four sides of the accommodation portion 204includes two first sealing portions 2021, on which the electrode leads15 are disposed, and two sealing portions 2022 on which the electrodeleads 15 are not disposed.

The battery cell 10 according to this embodiment may constitute thesealing portion 202 while being folded at least once to improve bondingreliability of the sealing portion 202 and to significantly reduce anarea of the sealing portion 202.

The battery cell 10 refers to a chargeable and dischargeable nickelmetal hydride (Ni-MH) cell or lithium ion (Li-ion) cell, and generatescurrent. A plurality of battery cells 10 are disposed in a line on bothsurfaces of the unit plate 21 to be described later.

The unit plate 21 includes a plate portion, with which the accommodationportion 204 of the battery cell 10 is in surface-contact, and sideportions 23 disposed on both side surfaces of the plate portion 22 toprotect the second sealing portion 2022 of the battery cell 10.

The plate portion 22 is formed as a flat surface, and the side portion23 is formed to protrude upwardly and downwardly of the plate portion 22from both edge portions of the plate portion 22. Accordingly, the unitplate 21 may be formed such that a cross section, obtained by cuttingthe plate portion 22 and the side portion 23, has an H-beam shape.

As illustrated in FIG. 8, a connection portion 23 a of the plate portion22, connected to the side portion 23, may be formed to have a thicknessgreater than a thickness of the other portion to secure rigidity. Inthis case, heat of the plate portion 22 may be more effectivelytransferred to the side portion 23. In addition, the entire externalsurface of the side portion 23 is disposed to face the third plate 50provided with a cooling device, and is disposed to be significantlyclose to the third plate 50. Therefore, the heat transferred to the sideportion 23 may be rapidly discharged to an external entity through thethird plate 50.

A shape of the above-described connection portion 23 a is not limited toa shape illustrated in the drawing, and may be variously modified asnecessary, for example, forming an empty space in the connection portion23 a, or the like.

The unit plate 21 according to this embodiment has one surface, on whichthree battery cells 10 arranged in a line, and the other surface onwhich three battery cells 10 arranged in a line. Therefore, a total ofsix battery cells 10 are coupled to each other in a single unit plate21. However, the present disclosure is not limited thereto, and one ortwo battery cells 10 may be disposed on each of both surfaces of theunit plate 21. As necessary, four or more battery cells 10 may bedisposed on each of both surfaces of the unit plate 21.

As three battery cells 10 are disposed on each of both surfaces of theunit plate 21, the unit plate 21 has three battery cell receiving spacesR1, R2, and R3 on one surface thereof.

Each of the receiving spaces R1, R2, and R3 is defined by the plateportion 22 and the side portions 23. A connection member 26, to whichthe electrode lead 15 of the battery cell 10 is connected, is disposedbetween the receiving spaces R1, R2, and R3.

Referring to FIGS. 4 and 5, the connection member 26 may include abusbar 26 a, formed of a conductive material, and a bracket 26 b formedof an insulating material.

The bracket 26 b is disposed along the circumference of a busbar 26 a,and is in contact with the unit plate 21 when the connection member 26is coupled to the unit plate 21. Therefore, when the connection member26 is coupled to the unit plate 21, the busbar 26 a is spaced apart fromthe unit plate 21, and thus, is not in direct contact with or notelectrically connected to the unit plate 21.

The busbar 26 a is formed of a flat metal plate, and has both surfacesexposed outwardly of the bracket 26 b. Therefore, the battery cells 10are bonded to both surfaces of the busbar 26 a to be electricallyconnected to each other.

In this embodiment, two battery cells 10 are connected to one surface ofthe busbar 26 a, and thus, a total of four battery cells 10 areconnected to one busbar 26 a.

The electrode lead 15 of the battery cell 10 is bent to be bonded to thebusbar 26 a by welding, or the like. However, a method of bonding theelectrode lead 15 of the battery cell 10 is not limited thereto.

The busbar 26 a and the bracket 26 b may be manufactured through insertinjection. However, a method of manufacturing the busbar 26 a and thebracket 26 b is not limited thereto, and the busbar 26 a and the bracket26 b may be coupled to each other after being individually manufactured.

The unit plate 21 is provided with a coupling hole 22 a in which theconnection member 26 is coupled between the receiving spaces R1, R2, andR3. When the connection member 26 is coupled to the coupling hole 22 a,the busbar 26 a of the connection member 26 and the plate portion 22 maybe disposed on the same plane, as illustrated in FIG. 5.

In this embodiment, the connection member 26 is coupled to the unitplate 21 in such a manner that the bracket 26 b is fitted into thecoupling hole 22 a formed in the unit plate 21. An adhesive may beinterposed between the connection member 26 and the unit plate 21 tostably couple the connection member 26 to the unit plate 21. Asnecessary, an additional fixing member such as a bolt or a screw may beused.

In the unit plate 21, two battery cells 10, disposed on both surfaces ofthe plate portion 22 to oppose each other with the plate portion 22interposed therebetween, are connected in parallel through theconnection member 26. In addition, three battery cells 10, disposed in aline on one of the surfaces of the unit plate 21, are connected inseries through the connection member 26. Accordingly, in a single cellunit 20, a plurality of battery cells 10 are connected in parallel whiletwo battery cells 10 constitute a pair, and the three battery cells 10connected in parallel are connected in series.

As illustrated in FIG. 3, the unit plate 21 according to this embodimentis provided with fastening grooves 22 b formed between the receivingspaces R1, R2, and R3 and the receiving space R1, R2, and R3, forexample, in a portion in which the connection member 26 is disposed.

More specifically, the coupling groove 22 b is formed in an externalside of the connection member 26 as a groove formed in such a mannerthat the plate portion 22 and the side portion 23 are removed.Therefore, the fastening groove 22 b is formed in such a manner that awidth of the plate portion 22 or the cell unit 20 is reduced, and theside portion 23 is discontinuously disposed by the fastening groove 22b.

The fastening groove 22 b is a region in which a fastening portion 55 ofthe case 40, to be described later, is disposed. Therefore, thefastening groove 22 b is formed to have a size at which the fasteningportion 55 may be easily disposed.

An external connection member 27 is disposed on both end portions of theunit plate 21. Similarly to the above-described connection member 26,the external connection member 27 may include a bracket and a busbar.

Only two battery cells 10, disposed to oppose each other with the plateportion 22 interposed therebetween, are connected to a busbar 27 a ofthe external connection member 27. The other portion of the busbar 27 ais used as a terminal 271 electrically connecting the cell units 20 toeach other (hereinafter referred to as a coupling terminal 271).

In the busbar 27 a of the external connection member 27, a portion usedas the coupling terminal 271 is disposed to protrude outwardly of theunit plate 21 and to be bent upwardly or downwardly of the plate portion22.

The coupling terminal 271 is coupled to the coupling terminal 271 ofanother cell unit 20. Accordingly, the plurality of cell units 20 may beconnected to each other in series or parallel through the couplingterminal 271. Welding or a fixing member such as a bolt or a screw maybe used to connect the coupling terminals 271 to each other, but thepresent disclosure is not limited thereto.

The above-configured unit plate 21 serves as a cooling plate whilesupporting the battery cell 10. Heat, generated in the battery cell 10,is transferred to a third plate 50 to be described later through theplate portion 22 and the side portion 23 of the unit plate 21. In thisembodiment, the third plate 50 serves as a cooling member. Accordingly,the heat of the battery cells 10 disposed on both sides of the plateportion 22 may be rapidly dissipated.

The circuit board 28 is connected to the busbar 26 a of each of theconnection members 26 to measure a voltage of the battery cell 10. Thecircuit board 28 may be provided with at least one temperature sensor 28a to measure a temperature of a battery and may further include a fuse,as necessary.

The temperature sensor 28 a may be disposed to be in contact with theaccommodation portion 204 or the sealing portion 202 of the battery cell10, but the present disclosure is not limited thereto. In thisembodiment, a negative temperature coefficient-thermal resistor (an NTCthermistor) is used as the temperature sensor 28 a, but the presentdisclosure is not limited thereto.

The circuit board 28 should be electrically connected to an outside ofthe battery module to detect a voltage or a temperature of the batterycell from the outside of the battery module 100. Thus, the circuit board28 should connect the temperature sensor 28 a and the busbar 26 a to theoutside of the battery module.

To this end, the circuit board 28 according to this embodiment is formedas a flexible circuit board (FPCB). As illustrated in FIG. 8, thecircuit board 28, disposed in the receiving spaces R1, R2, and R3, isdisposed between the battery cell 10 and the side portion 23. Morespecifically, the circuit board 28 is attached to an internal sidesurface of the side portion 23 to be led outwardly of the unit plate 21along the side portion 23. The circuit board 28, attached to theinternal side surface of the side portion 23, may be firmly bonded tothe side portion 23 through an adhesive or an adhesive tape.

A section, disposed in the receiving spaces R1, R2, and R3 of thecircuit board 28, has a width less than a width of the side portion 23.Therefore, even when the circuit board 28 is disposed on the internalside surface of the side portion 23, the circuit board 28 is not exposedoutwardly of the side portion 23.

Accordingly, the circuit board 28 may be led outwardly of the unit plate21 without interference with the battery cell 10.

In the circuit board 28, a portion led outwardly of the unit plate 21may be connected to an external entity through a connector, notillustrated, provided in a cover plate 70 to be described later.

The cell assembly 60 according to this embodiment is configured bystacking a plurality of cell units 20.

To this end, the cell assembly 60 includes a coupling unit 30 disposedbetween the cell units 20.

As illustrated in FIG. 7, the coupling unit 30 is disposed between twocell units 20, stacked in a vertical direction, to be fixedly coupled tothe two cell units 20.

The coupling unit 30 may include a frame 31, disposed between the sideportions 23 of the unit plate 21, and support portions 32 and 33disposed on the end portions of the frame 31.

The support portions 32 and 33 may include a first support 32 and asecond support 33.

The first support portion 32 supports both end portions of the cell unit20. When the first support portion 32 is disposed between the couplingterminals 271 of the cell unit 20 to electrically connect the couplingterminals 271 to each other, the firs support portion 32 may serve tofix the coupling terminals 271. To this end, the first support 32 may beprovided with a fastening hole 36 in which a coupling member such as abolt or screw, used when the coupling terminals 271 are coupled, isfastened. Accordingly, the fixing member penetrates through both of thetwo coupling terminals 271 and the fastening hole 36 to fixedly couplethe coupling terminals 271 to the first support portion 32.

The first support 32 is provided with a first protrusion 34 protrudingupwardly of the first support 32. The first protrusion 34 is providedfor easy coupling to the external connection member 27 of the cell unit20 stacked on the first protrusion 34. The first protrusion 34 may beinserted into a hole provided in the unit plate 21 or the externalconnection member 27.

The second support portion 33 is disposed between the connection members26 of the cell unit 20 to support the connection member 26. Accordingly,when both end potions of the frame 31 are disposed between theconnection members 26, second supports 33 may be disposed on both endportions of the frame 31, respectively.

The second support portion 33 may be configured to be coupled to andseparated from a second support portion 33 of another frame 31. Forexample, the second support portion 33 may be configured to be fitted inand coupled to the second support 33 of another frame 31. However, theconfiguration of the second support portion 33 is not limited thereto,and the second supports 33 may be coupled to each other using anadditional fixing member.

In addition, the second support portion 33 may be provided with a secondprotrusion 35 for easy coupling to the connection member 26. Similarly,the second protrusion 35 may also be configured to be inserted into ahole provided in the unit plate 21 or the connection member 26.

As described above, the first protrusion 34 and the second protrusion 35define a coupled location of the cell unit 20. Accordingly, the cellunit 20 and the coupling unit 30 may be easily aligned and coupled toeach other while assembling the cell assembly 60.

The frame 31 is formed to have a rectangular ring shape along a contourof the battery cell 10, and is disposed between the side portions 23 ofthe cell units 20 stacked in a vertical direction.

An inside of the frame 31 is formed as an empty space. Therefore, asillustrated in FIG. 8, when the cell units 20 are coupled to thecoupling unit 30, a portion of the battery cell 10 coupled to the cellunit 20 is accommodated in the internal space of the frame 31. Forexample, when the battery cell 10 is coupled to the unit plate 21, aportion of the accommodation portion 204 of the battery cell 10protrudes outwardly of the receiving spaces R1, R2, and R3 of the unitplate 21. The protruding portion is disposed in the internal space ofthe frame 31 of the coupling unit 30.

The coupling unit 30 according to this embodiment is provided with aplurality of frames 31. More specifically, the frames 31 are provided asmany as the number of battery cells 10 arranged in a line in the cellunit 20 to be coupled to the coupling unit 30. Accordingly, in thisembodiment, each of the coupling units 30 is provided with three frames.However, the number thereof is not limited thereto. An insulating pad 18may be disposed between the battery cells 10, opposing each other, inthe internal space of the frame 31.

The insulating pad 18 is formed of a compressed pad or a foam materialto prevent direct contact between battery cells and to increaseinsulation. In addition, an assembly tolerance may be absorbed during amanufacturing process to enhance ease of assembling.

However, an example of the insulating pad 18 is not limited thereto, andvarious modifications, such as an insulating pad 18 formed of adouble-sided adhesive tape or adhesive resin, may be made.

The insulating pad 18 a, disposed between the cell assembly 60 and thefirst and second plates 40 a and 40 b, serves to prevent the overallvolume of the battery cells from expanding when a specific battery cellexpands. Can perform the function. Thus, the insulating pad 18 a,disposed between the cell assembly 60 and the first and second plates 40a and 40 b, may be formed of polyurethane foam. However, a material ofthe insulating pad 18 a is not limited thereto.

The case 40 may include a first plate 40 a coupled to a lower portion ofthe assembly 60, a second plate 40 b coupled to an upper portion of thecell assembly 60, a third plate 50 coupled to a side surface of the cellassembly 60, and a cover plate 70, as illustrated in FIG. 2.

At least one of the first, second, and third plates 40 a, 40 b, 50 mayserve as a cooling member of the battery module 100. In this embodiment,the third plate 50 serves as a cooling member However, the configurationof the present disclosure is not limited thereto, and the first plate 40a or the second plate 40 b may also be configured to serve as a coolingmember having the same shape as the third plate 50, depending on a sizeof the battery cell 10.

To this end, the first, second, and third plates 40 a, 40 b, 50 may beformed of a material having high thermal conductivity such as metal. Forexample, the first, second, and third plates 40 a, 40 b, and 50 may beformed of aluminum. However, a material thereof is not limited thereto,and various materials may be used as long as the material has similarstrength and thermal conductivity even if the material is not a metal.

The first plate 40 a is disposed below the cell assembly 60 to supportlower surfaces of the battery cells 10, and the second plate 40 b isdisposed above the cell assembly 60 to cover upper surfaces of batterycells 10. The third plate 50 is disposed on each of both side surfacesof the cell assembly 60 to be coupled to the first plate 40 a and thesecond plate 40 b. Thus, the first, second, and third plates 40 a, 40 b,and 50 constitute a tubular case.

The third plate 50 protects a side surface of the cell assembly 60, andcools the battery cell 10. To this end, the third plate 50 includes aninternal plate 50 a and an external plate 50 b, as illustrated in FIG.8.

The internal plate 50 a is disposed on a side of the cell assembly 60,and the external plate 50 b is disposed on an external side of theinternal plate 50 a and coupled to the external surface of the internalplate 50 a.

The inner plate 50 a is coupled to the above-described first and secondplates 40 a and 40 b. The external plate 50 b is bonded to an externalsurface of the internal plate 50 a. In this case, the entirety of theexternal plate 50 b may not be bonded and at least a portion thereof maybe bonded. At least a portion of the unbonded portion may be spacedapart from the internal plate 50 a. Thus, a space is formed between theinternal plate 50 a and the external plate 50 b to be used as a coolingflow path (S in FIG. 8).

The external plate 50 b may be bonded to the internal plate 50 a throughwelding or brazing. As necessary, the external plate 50 b may be bondedto internal plate 50 a using an adhesive.

The cooling flow path S is disposed in the entire external plate 50 b. Ashape of the cooling passage S may be variously modified, as necessary.

The above-configured external plate 50 b may be manufactured by pressinga metal plate. In this embodiment, the internal plate 50 a and theexternal plate 50 b are formed of the same material (for example,aluminum). However, the material thereof is not limited thereto, and theinternal plate 50 a and the external plate 50 b may be formed ofdifferent materials to each other.

In this embodiment, one side of the internal plate 50 a is provided withan inlet 52 and an outlet 54 of a cooling flow path 5. Accordingly,cooling water is introduced into the above-described cooling flow path Sthrough the inlet 52 and passes through the cooling flow path S, and isthen discharged outwardly of the cooling flow path S through the outlet54. However, the configuration of the present disclosure is not limitedthereto. As necessary, locations of the outlet 54 and the inlet 52 maybe variously modified. For example, the outlet 54 and the inlet 52 maybe disposed on the external plate 50 b or the external plate 50 b, ormay be disposed the external plate 50 b and the external plate 50 b,respectively.

The third plate 50 according to this embodiment is used as awater-cooled cooling device having a cooling flow path S therein.However, the configuration of the present disclosure is not limitedthereto, and an air-cooled cooling device may be applied.

Referring to FIG. 2, in the third plate 50 according to this embodiment,a fastening portion 55 is formed on an internal surface opposing thecell assembly 60. The fastening portion 55 is disposed to protrude fromthe internal surface of the third plate 50 to a side of the cellassembly 60, and has a fastening hole 55 a formed therein.

The fastening portion 55 is formed to have a pipe shape to be bonded toan internal surface of the third plate 50. In this case, the fasteningportion 55 is disposed to be inserted into the coupling groove (22 b inFIG. 3) of the above-described unit plate 21. Accordingly, the couplingportion 55 has a size enough to be insertable into the coupling groove22 b. Each of the first plate 40 a and the second plate 40 b is providedwith a through-hole into which the fastening member 65 is inserted in alocation corresponding to the fastening grooves 22 b.

As the cell unit 20 is stacked in a vertical direction, the fasteninggroove 22 b is formed to penetrate through the cell assembly 60 in thevertical direction. Accordingly, the coupling portion 55 is alsodisposed in the coupling groove 22 b to penetrate through the cellassembly 60 in the vertical direction.

The fastening hole 55 a is a hole, into which the fastening member 65such as a bolt or a screw is inserted and coupled, and is used to fixthe battery module 100 to a structure or the like.

The fastening member 65 sequentially penetrates through the first plate40 a, the fastening hole 55 a of the third plate 50, and the secondplate 40 b to be fixedly fastened to the second plates 40 a and 40 b.

In the fastening member 65, a portion protruding downwardly of thesecond plate 40 b is fastened to a structure (for example, a vehicle, orthe like) in which the battery module 100 is mounted.

When the fastening portion 55 is not provided, it may be difficult tosecure rigidity of the third plate 50 in the vertical direction. In thiscase, when external force is applied to the battery module 100 in thevertical direction, the second plate 4 0 b is readily damaged. Forexample, the third plate 50 may also be deformed by a force applied tofasten the fastening member 65 to the structure.

However, as in this embodiment, when the fastening portion 55 isprovided and the first plate 40 a and the second plate 40 b arerespectively disposed below and above the coupling portion 55, thefastening member 65 sequentially penetrates through the first plate 40a, the fastening portion 55, and the second plate 40 b to be fastened tothe structure.

Accordingly, even when an external force is applied in the verticaldirection, the third plate 50 is not readily deformed by the fasteningportion 55 disposed between the first plate 40 a and the second plate 40b.

In addition, the fastening portion 55 is inserted into the fasteninggroove 22 b. When the fastening groove 22 b is not present, a distancebetween the third plates 50 should be increased or the fastening portion55 should be disposed on an external surface of the third plate 50,rather than an internal surface of the third plate 50. In this case, avolume of the battery module may be increased.

However, since the battery module 100 according to this embodiment isprovided with a fastening groove 22 b in the unit plate 21, thefastening portion 55 may be disposed in a space formed in the cellassembly 60. Thus, the above-mentioned issues may be addressed.

Referring to FIG. 8, a heat transfer member 59 may be disposed betweenthe cell assembly 60 and the case 40.

In this embodiment, the heat transfer member 59 is disposed between thecell assembly 60 and the third plate 50. Specifically, the heat transfermember 59 is disposed between an external surface of the side portion 23and an internal surface of an internal side plate 50 a of the thirdplate 50. However, a location of the heat transfer member 59 is notlimited thereto, and the heat transfer member 59 may be disposed onsides of the first and second plate 40 a and 40 b, as necessary.

The heat transfer member 59 may be formed of a material having high heatconductivity. In addition, the heat transfer member 59 may be formed ofthermal grease, a thermally conductive adhesive formed of an epoxy-basedresin, a urethane-based, a silicone-based resin, or an acryl-basedresin, and a pad.

The heat transfer member 59 may be formed by applying a liquid orgel-state material to the internal surface of the third plate 50.Accordingly, the heat transfer member 59 is disposed to fill a spacebetween the cell assembly 60 and the third plate. However, a location ofthe heat transfer member 59 is not limited thereto, and a pad-shapedheat transfer member 59 may be inserted.

The heat transfer member 59 absorbs an assembly tolerance between thecell assembly 60 and the third plate 50. Thus, the cell assembly 60 maybe firmly fixed to the case 40 in an internal space of the case 40 bythe heat transfer member 59, and heat dissipated from the cell assembly60 may be rapidly transferred to the third plate 50 through the heattransfer member 59. In addition, as the heat transfer member 59 isdisposed between the cell assembly 60 and the case 40, overall rigidityof the battery module 100 may be enhanced.

The third plate 50 according to this embodiment may include areinforcing plate 50 c coupled to an external surface of the externalside plate 50 b.

The reinforcing plate 50 c is provided to reinforce the rigidity of thesecond plate 40 b. Therefore, the reinforcing plate 50 c is coupled tothe external plate 50 b to cover an entire external surface of theexternal plate 50 b, and is formed of a material having rigidity greaterthan rigidity of the internal plate 50 a or the external plate 50 b.

For example, the reinforcing plate 50 c may be formed of anultrahigh-strength steel sheet having tensile strength of 1 giga Pascal(GPa) or more, but the present disclosure is not limited thereto.

The cover plate 70 is coupled to each of both end portions of the cellassembly 60.

The cover plate 70 is coupled to the first, second, and third plates 40a, 40 b, 50 to complete an exterior of the battery module 100.

The cover plate 70 may be formed of an insulating material such asresin, and may be provided with a groove or a hole for exposing theconnection terminal 272 to an external entity. The connection terminal272 may be used to electrically connect the battery module to anexternal entity, and may be one of the coupling terminals 271 providedin the cell unit 20. In addition, the cover plate 70 may be providedwith a connector, not illustrated, connected to the circuit board 28.

The cover plate 70 may be coupled to the first, second, third plate 40a, 40 b, and 50 through a fixing member such as a screw or a bolt.However, coupling of the cover plate 70 is not limited thereto.

An insulating cover 80 and a flow path connection portion 90 may bedisposed between the cover plate 70 and the cell assembly 60.

The insulation cover 80 is formed of an insulating material and iscoupled to both ends of the cell assembly 60, to which the couplingterminals 271 are coupled, to protect the coupling terminals 271 of thecell assembly 60 and to maintain insulation.

At least one of the insulating cover 80 may be provided with a hole 82through which the connection terminal 72 is disposed. The connectionterminal 72 is exposed to an external entity through the hole 82 formedin the insulating cover 80. Therefore, the through hole 82 of theinsulating cover 80 is formed to have a size corresponding to a size anda shape of the connection terminal 272.

Although not illustrated, a heat transfer member may fill a spacebetween the insulating cover 80 and the cell assembly 60, as necessary.

The flow path connection portion 90 is disposed between the insulatingcover 80 and the cover plate 70 and has a flow path through which thecooling water passes. The flow path of the flow path connection portion90 is connected to each of the inlet 52 and the outlet 54 provided inthe third plate 50.

The flow path connection portion 90 is used as a path for supplyingcooling water to the battery module 100 from a device or equipment inwhich the battery module 100 is mounted. To this end, a flow path of theflow path connection portion 90 includes an inlet and outlet 92connected to an external entity.

Accordingly, the cooling water supplied to the flow path connectionportion 90 through the inlet and outlet 92 is supplied to the coolingflow path S of the third plate 50 through the inlet 52 of the thirdplate 50. The cooling water, passing through the cooling flow path S,returns to the flow path connection portion 90 and is then dischargedoutwardly of the battery module 100 through the inlet and outlet 92.

In the above-configured battery module 100 according to this embodiment,cooling devices are disposed on both sides of the cell assembly 60,respectively. Since the unit plate 21 is disposed between the batterycells 10, heat may be rapidly transferred to the cooling devices throughthe unit plate 21. Thus, heat generated in the battery cell 10 may beeffectively dissipated.

In addition, since the cell assembly 60 is completed by stacking aplurality of cell units 20, the battery module 100 may be easilymanufactured, and the battery module 100 may be manufactured to havevarious sizes and capacities depending on the number of cell units 20.

In addition, since the third case is provided with a cooling flow pathS, the cell assembly 60 and the cooling channel S are disposed as closeas possible, and thus, cooling efficiency of the cell assembly 60 may beenhanced.

As described above, since a battery module according to an exampleembodiment includes a unit plate disposed between battery cells, heatmay be rapidly transferred to a side of a cooling device through theunit plate. Thus, heat generated in the battery cell may be effectivelydissipated.

In addition, since a cell assembly is completed by stacking a pluralityof cell units, the battery module may be easily manufactured.

While this disclosure includes specific examples, it will be apparentafter an understanding of the disclosure of this application thatvarious changes in forms and details may be made in these exampleswithout departing from the spirit and scope of the claims and theirequivalents. The examples described herein are to be considered in adescriptive sense only, and not for purposes of limitation. Descriptionsof features or aspects in each example are to be considered as beingapplicable to similar features or aspects in other examples. Suitableresults may be achieved if the described techniques are performed in adifferent order, and/or if components in a described system,architecture, device, or circuit are combined in a different manner,and/or replaced or supplemented by other components or theirequivalents. Therefore, the scope of the disclosure is defined not bythe detailed description, but by the claims and their equivalents, andall variations within the scope of the claims and their equivalents areto be construed as being included in the disclosure.

What is claimed is:
 1. A battery module comprising: a cell unitincluding a plurality of battery cells disposed on both surfaces of aunit plate; and a case accommodating the cell unit and provided with acooling device on at least one surface of the case, wherein the unitplate comprises a plurality of receiving spaces each formed by a plateportion having a flat surface and a side portion protruding upwardly anddownwardly of the plate portion from both sides of the plate portion,and the plurality of battery cells are received in each of the receivingspaces.
 2. The battery module of claim 1, wherein the case comprises: afirst plate disposed above the cell unit; a second plate disposed belowthe cell unit; and a third plate disposed on a side portion of the cellunit and including the cooling device.
 3. The battery module of claim 2,wherein the side portion has an external surface disposed to oppose thethird plate.
 4. The battery module of claim 3, further comprising: aheat transfer member disposed between the side portion and the thirdplate.
 5. The battery module of claim 4, wherein the heat transfermember is formed of one of thermal grease, a thermally conductiveadhesive, and a pad.
 6. The battery module of claim 3, wherein the thirdplate comprises: an internal side plate disposed to oppose the cellunit; an external side plate disposed outside of the internal side plateto be in contact with the internal side plate; and a cooling flow pathprovided between the internal side plate and the external side plate. 7.The battery module of claim 6, wherein the third plate further comprisesa reinforcing plate coupled to the external side plate while covering anexternal surface of the external side plate and formed of a materialhaving greater rigidity than that of the external side plate.
 8. Thebattery module of claim 7, wherein the third plate is formed ofaluminum, and the reinforcing plate is formed of an ultrahigh-strengthsteel sheet.
 9. The battery module of claim 1, wherein in the plateportion of the unit plate, a portion connected to the side portion isformed to have a large thickness.
 10. The battery module of claim 1,wherein the cell unit includes three pairs of battery cells, the batterycells in each pair being connected to each other in parallel, and thebattery cells on each one surface of the unit plate being connected inseries.
 11. The battery module of claim 1, wherein the plurality ofbattery cells are disposed in pairs symmetrically on both surfaces ofthe unit plate, and wherein the battery cells in each pair are connectedelectrically in parallel.
 12. The battery module of claim 1, wherein thereceiving spaces include first, and second receiving spaces on each sideof the unit plate, wherein a connection member is disposed in a couplinggroove between the first and second receiving spaces; and wherein theconnection portion connects the battery cells of the first receivingspace with corresponding battery cells of the second receiving space inseries electrically, and connects the batterie cells of the firstreceiving portion in parallel to each other.
 13. A cell unit comprising:a unit plate including a plurality of receiving space structuresmechanically connected in series, each receiving space structure havinga plate portion and a pair of receiving spaces formed at oppositesurfaces of the plate portion, each receiving space being configured toreceive a battery cell; and a plurality of connection members disposedbetween consecutive receiving space structures, wherein each connectionmember couples the battery cells in each pair of receiving spaceselectrically in parallel to each other and battery cells accommodated inconsecutive receiving space structures and which are positioned at asame surface of the corresponding plate portion electrically in seriesto each other.
 14. The cell unit of claim 13, wherein each connectionmember includes a busbar formed of a conductive material and a bracketformed of an insulating material, and wherein the bracket is disposedalong the circumference of the busbar, and is in contact with the plateportion when the connection member is coupled to the plate portion. 15.The cell unit of claim 14, further comprising a circuit board connectedto the busbar of each of the connection members, the circuit boardincluding at least one temperature sensor.
 16. The cell unit of claim13, wherein each unit plate is provided with a coupling hole in which acorresponding connection member is coupled.
 17. The cell unit of claim16, wherein when the corresponding connection member is coupled to thecoupling hole, a busbar of the connection member and the plate portionare disposed on the same plane.
 18. The cell unit of claim 13, furthercomprising an external connection member disposed on both end portionsof the unit plate, each external connection member including a bracketand a busbar.
 19. The cell unit of claim 18, wherein in the busbar ofthe external connection member, a portion is used as a coupling terminalto be coupled to another coupling terminal of another cell unit so thata plurality of cell units are connected to each other in series orparallel through the coupling terminals.
 20. The cell unit of claim 13,wherein the unit plate serves to dissipate heat generated in the batterycells to a cooling plate.